Work around for nexus 6 TexSubImage issue

BUG=skia:

Review URL: https://codereview.chromium.org/1173203005

2 files changed, 20 insertions, 12 deletions

diff --git a/include/gpu/GrCaps.h b/include/gpu/GrCaps.h
index 54969c5933..c5789fc0dc 100644
--- a/include/gpu/GrCaps.h
+++ b/include/gpu/GrCaps.h
@@ -133,6 +133,9 @@ public:
     bool textureBarrierSupport() const { return fTextureBarrierSupport; }
 
     bool useDrawInsteadOfClear() const { return fUseDrawInsteadOfClear; }
+    bool useDrawInsteadOfPartialTextureWrite() const {
+        return fUseDrawInsteadOfPartialTextureWrite;
+    }
 
     /**
      * Indicates the capabilities of the fixed function blend unit.
@@ -220,18 +223,19 @@ protected:
 
     SkAutoTUnref<GrShaderCaps>    fShaderCaps;
 
-    bool fNPOTTextureTileSupport        : 1;
-    bool fMipMapSupport                 : 1;
-    bool fTwoSidedStencilSupport        : 1;
-    bool fStencilWrapOpsSupport         : 1;
-    bool fDiscardRenderTargetSupport    : 1;
-    bool fReuseScratchTextures          : 1;
-    bool fGpuTracingSupport             : 1;
-    bool fCompressedTexSubImageSupport  : 1;
-    bool fOversizedStencilSupport       : 1;
-    bool fTextureBarrierSupport         : 1;
+    bool fNPOTTextureTileSupport                : 1;
+    bool fMipMapSupport                         : 1;
+    bool fTwoSidedStencilSupport                : 1;
+    bool fStencilWrapOpsSupport                 : 1;
+    bool fDiscardRenderTargetSupport            : 1;
+    bool fReuseScratchTextures                  : 1;
+    bool fGpuTracingSupport                     : 1;
+    bool fCompressedTexSubImageSupport          : 1;
+    bool fOversizedStencilSupport               : 1;
+    bool fTextureBarrierSupport                 : 1;
     // Driver workaround
-    bool fUseDrawInsteadOfClear         : 1;
+    bool fUseDrawInsteadOfClear                 : 1;
+    bool fUseDrawInsteadOfPartialTextureWrite   : 1;
 
     BlendEquationSupport fBlendEquationSupport;
     uint32_t fAdvBlendEqBlacklist;
diff --git a/include/gpu/GrContextOptions.h b/include/gpu/GrContextOptions.h
index 057bc83d19..95b153fe61 100644
--- a/include/gpu/GrContextOptions.h
+++ b/include/gpu/GrContextOptions.h
@@ -17,7 +17,8 @@ struct GrContextOptions {
         , fMaxTextureSizeOverride(SK_MaxS32)
         , fMinTextureSizeOverride(0)
         , fSuppressDualSourceBlending(false)
-        , fGeometryBufferMapThreshold(-1) {}
+        , fGeometryBufferMapThreshold(-1)
+        , fUseDrawInsteadOfPartialTextureWrite(false) {}
 
     // EXPERIMENTAL
     // May be removed in the future, or may become standard depending
@@ -39,6 +40,9 @@ struct GrContextOptions {
         buffers to CPU memory in order to update them.  A value of -1 means the GrContext should
         deduce the optimal value for this platform. */
     int  fGeometryBufferMapThreshold;
+
+    /** some gpus have problems with partial texture writes */
+    bool fUseDrawInsteadOfPartialTextureWrite;
 };
 
 #endif